Starting January 31, 2019, the classic version of Yahoo Mail will no longer be available. At that time, you'll be upgraded to the latest version of Yahoo Mail or basic Mail, depending on your browser's compatibility. Learn more about the latest version of Yahoo Mail.

Fix POP or IMAP client sending and receiving issues

Third-party email clients, like Outlook and mac Mail, use either POP or IMAP protocols to connect to your Yahoo Mail account. These apps need a lot of things to align perfectly in order for them to work properly with an email account. Use these steps to identify and fix the source of the problem.

Step 1: Check if there's an issue with your account

You'll need to address any prompts or issues you see when doing the following before you can use your account in a third-party email app.

Step 2: Verify you're using the right POP or IMAP settings

Check that the app is configured with the correct POP settings or IMAP settings for Yahoo Mail. Sometimes even if the info seems correct, the data on the hard drive that the app saved could be corrupt or contain hidden invalid characters. You can delete your account from the app and re-add it to be sure. If you need specific instructions for your app, contact its manufacturer.

Step 3: Check for software that is blocking the ports we use

Firewalls, antivirus software, and network protocols have the ability to block ports. If any of our ports (995, 465, or 587) are blocked, the app can't connect to our servers. Check with your Internet Service Provider or your security software's manufacturer to learn how to check for and unblock ports.

Make sure you've verified any extra email addresses that you've added. Any unverified address can cause errors, such as a 553 error code, when sending from a third-party email app.

Follow the instructions you received at the extra address in order to complete the verification process.

Step 5: Contact your app manufacturer or use a different app

If you've verified that your account is working outside of the app and you've checked the other possible solutions, then there's something wrong with the app you're using. The app manufacturer may have additional troubleshooting steps to try. Alternatively, you can use a different third-party email app.